Pincers having adjustable jaws with locking pinion



April 22, 1958 A. GULDER 2,831,385

FINGERS HAVING ADJUSTABLE JAWS WITH LOCKING PINION Filed March 29. 1956 2 Sheets-Sheet 1 ll {I II I i: 1 :i

JNVENTOR.

April 22, 1958 A, GULDER 2,831,385

PINCERS HAVING ADJUSTABLE JAWS WITH LOCKING PINI-ON Filed March 29, 1956 2 sheets-sheet:

United States Patent PINCERS HAVING ADJUSTABLE JAWS WITH LOCKING PINION Application March 29, 1956, Serial No. 574,900 2 Claims. '(Cl. 81'-384) Many types of pincers with adjustable grasping jaws are already known. One type comprises a handle or shank which may' for example be equipped with a square thread and a nut, fitting into the same; by rotation of the nut the pivot of the pincers can be moved longitudinally on the threaded handle whereby both handles may be displaced wtih respect to each other.

The disadvantage of this construction is the continual adjustment necessary to enable the user to accomplish a tight grip of the piece to be turned.

Another type of pincers used for tightening or loosening nuts of various sizes consists of one handle forming an integral piece with the jaw, as usual, whereas the other handle only extends to the pivot which has a pinion mounted for rotation thereon. The pinion is permanent ly in mesh with a rack on the other jaw, and is slidably arranged in a dovetailed grove in the longer one of the two handles. This arrangement makes it possible to keep the gripping surfaces of the jaws parallel at all times. A spring controlled locking pin fitting into notches of the pinion is mounted for longitudinal sliding on the shorter handle. When that handle is pivoted with respect to the other handle, the pinion is turned and the jaws are displaced with respect to each other. For adjusting the desired spacing of the jaws, the locking pin is disengaged by one hand and the pinion is brought into the desired position by the other hand, whereupon the locking pin is allowed to fall into place on the pinion. I

The manufacture of such pincers with accurate guide means for one jaw in a groove is comparatively expensive. Furthermore, it is an inconvenience that upon gripping some piece the entire pressure has to be transmitted by the teeth of the pinion onto the rack of the movable aw.

It is an object of the present invention to overcome the abovementioned drawbacks of known pincers, and to provide an adjustable gripping tool which is simple and inexpensive to manufacture and of considerable practical advantage for grasping and turning any desired part, such as a pipe, a screwbolt, nut or the like.

According to the invention two pinions are provided, both mounted on one handle of the pincers and in mesh with each other as well as with a rack arranged at the rear side of the other handle. The pinions serve for locking the pincers, wtih the jaws in an adjusted spacing from each other. One of these pinions is mounted on a pin which is at the same time the pivot point for the pincers. This pinion is in permanent engagement with the rack on the other handle. The other pinion is disengageable from the rack by means of a locking lever, pivotally mounted on the movable handle and biased by a spring into locking position. The mounting pin of the locking pinion can be moved in slots provided in the moveable handle on the one hand and in the locking lever on the other hand, said slots being arranged at right angles with respect to each other.

It is another feature of the present invention thatthe locking lever engages the handle comprising the rack "ice from both sides with so much clearance that disengagement of the locking lever may be achieved by pressing an extension of the lever in the direction of the jaws, or by pressing the two handles apart. This arrangement makes it possible to guide the jaws during the adjustment of the gripping surfaces in parallel with respect to each other and to operate'the pincers with one hand.

Further advantages are simple and rapid coarse adjustment and positive engagement of the jaws with the article to be gripped, due to a favorable proportioning of the lever arms.

Other particulars and advantages will become apparent from the following description and the accompanying drawings.

The invention will now be more fully described with reference to the accompanying drawings, but it should be understood that this is given by way of illustration and not of limitation and that many changes may be made in the details without departing from the spirit of the invention.

In the drawings:

Fig. 1 shows the pincers in side elevation;

Fig. 2 is a rear view of the same;

Fig. 3 is a side view of the pincers with the pinions out of mesh, and

Fig. 4 is a view of the locking lever.

Referring now to Fig. 1, the pincers are shown to comprise a jaw 1, forming an integral part with a handle 2 provided with a row of teeth 3 forming a rack. The other handle of the pincers is designated by 5 and is integral with a jaw 4. This handle is adjustable and comprises two pins, 6 and 7, fixedly secured thereto. In a recessed portion 8 of handle 5 an adjusting pinion 9, a locking pinion 10, a locking lever 11 and a spring 12 are housed. The pinion 9 is rotatably mounted on pin 6, which also forms the articulating member for the pincers, and pinion 9 is permanently in mesh with rack 3 of handle 2. The locking pinion 10 is mounted on a pin 13 which is slideably arranged in a slot 14 of handle 5, being at the same time guided in a slot 15 oflever 11, extending perpendicularly with respect to slot 14. That lever which engages the handle 2 and is at its free end provided with a projecting lip 16 serving as a handle, is constantly biased into locking position by a spring 12.

From Fig. l which shows the locking lever 11 and the pinions 9 and 10 in locking position, it may be seen that in this position both pinions are in mesh with each other and with rack 3. In this manner, the pinions lock each other, so that they are not rotatable in any direction on their pins 6 or 13 respectively. The distance between the twoijaws of the pincers is determined and fixed thereby.

If it is desired to change the gripping distance, the lip 16 of locking lever 11 may either be pressed in the direction toward the jaws, or alternatively, the two handles 2 and 5 of the pincers are pressed apart as shown in Fig. 3. In both cases it is brought about that locking lever 11 is turned on pin 7, whereby pinion 10 is disengaged from rack 3 with simultaneous shift of its axis 13 in slots 14 and 15. At the same time pinion 9 will become unlocked and is capable of rolling along rack 3, with the result that handle 5 can be moved into a position which corresponds to the desired spacing of the jaws. As soon as lip 16 of lever 11 is released, or the two handles 2 and 5 are approached, the locking lever 11 is returned by spring 12 into locking position, whereby pinion 10 will again be brought into engagement with rack 3.

What I claim is:

1. Pincers with adjustable jaws of the type having two.

handles capable of adjustment with respect to each other, a rack on the first handle and means on the second handle for engagement with said rack and adjustable thereon, whereby the spacing of the jaws is likewise adjusted, said means comprising an adjusting pinion and a locking pinion in mesh with each other, each pinion mounted for rotation on a pin secured to said second handle, said pin for the adjusting pinion also being the pivot of said pincers, said adjustable pinion being in mesh with said rack constantlyand said locking pinion being disengageable from said rack whereby said adjust able pinion is released for rolling movement on said rack to a new position of adjustment, and as means for disengagement of said locking pinion a lever mounted on a third pin associated with spring means for urging said lever to return into locked position, whereby said pinion is brought into engagement with the rack, said second handle and said lever having slots extending at right angles to each other for moving therein of said pin of the locking pinion upon movement to and from the rack.

2. In pincers according to claim 1, a projection on said lever for grasping the same during its actuation into a pinion-operating position.

References Cited in the. file of this patent UNITED STATES PATENTS 137,908 Frank Apr. 15, 1873 598,588 Whitehead Feb. 8, 1898 1,302,009 Carroll Apr. 29, 1919 1,438,641 Gazlay Dec. 12, 1922 1,456,208 Armstrong May 22, 1923 1,460,294 Wegner June 26,1923 1,561,681 B.a,r nes Nov. 17, 1925. 

